To meet a demand for radio data traffic that is on an increasing trend since commercialization of a 4G communication system, efforts to develop an improved 5G communication system or a pre-5G communication system have been conducted. For this reason, the 5G communication system or the pre-5G communication system is called a communication system beyond 4G network or a system since the post LTE. To achieve a high data transmission rate, the 5G communication system is considered to be implemented in a super high frequency (mmWave) band (for example, like 60 GHz band). To relieve a path loss of a radio wave and increase a transfer distance of a radio wave in the super high frequency band, in the 5G communication system, beamforming, massive MIMO, full dimensional MIMO (FD-MIMO), array antenna, analog beam-forming, large scale antenna technologies have been discussed. Further, to improve a network of the system, in the 5G communication system, technologies such as advanced small cell, cloud radio access network cloud (RAN), ultra-dense network, device to device communication (D2D), wireless backhaul, moving network, cooperative communication, coordinated multi-points (CoMP), and interference cancellation have been developed. In addition to this, in the 5G system, hybrid FSK and QAM modulation (FQAM) and sliding window superposition coding (SWSC) that are an advanced coding modulation (ACM) scheme and a filter bank multi carrier (FBMC), a non orthogonal multiple access (NOMA), and a sparse code multiple access (SCMA) which are an advanced access technology, and so on have been developed.
Meanwhile, the Internet is evolved to an Internet of Things (IoT) network that transmits and receives information, such as things, between distributed components and processes the information, in a human-centered connection network through which a human being generates and consumes information. The Internet of Everything (IoE) technology in which the big data processing technology, etc., by connection with a cloud server, etc., is combined with the IoT technology has also emerged. To implement the IoT, technology elements, such as a sensing technology, wired and wireless communication and network infrastructure, a service interface technology, and a security technology, have been required. Recently, technologies such as a sensor network, machine to machine (M2M), and machine type communication (MTC) for connecting between things has been researched. In the IoT environment, an intelligent Internet technology (IT) service that creates a new value in human life by collecting and analyzing data generated in the connected things may be provided. The IoT may be applied to fields, such as a smart home, a smart building, a smart city, a smart car or a connected car, a smart grid, health care, smart appliances, and an advanced healthcare service by fusing and combining the existing information technology (IT) with various industries.
Therefore, various tries to apply the 5G communication system to the IoT network have been conducted. For example, the 5G communication technologies such as the technologies of the sensor network, the machine to machine (M2M), the machine type communication (MTC) are implemented by techniques such as the beam-forming, the MIMO, the array antenna, or the like. An example of the application of the cloud radio access network (cloud RAN) as the big data processing technology described above may also be the fusing of the 5G technology with the IoT technology.
A current mobile communication system has been developed from a mobile communication system providing a voice centered service in the early stage toward high-speed, high-quality wireless packet data communication system for providing a data service and a multimedia service. For this purpose, various standardization organizations such as 3GPP, 3GPP2, and IEEE have progressed a 3rd advanced mobile communication system standard to which a multiple access scheme using a multi-carrier is applied. Recently, various mobile communication standards such as long term evolution (LTE) of the 3GPP, ultra mobile broadband (UMB) of the 3GPP2, and 802.16m of the IEEE have been developed to support a high-speed, high-quality wireless radio data transmission service based on the multiple access scheme using the multi-carrier.
The existing 3rd advanced mobile communication systems such as LTE, UMB, and 802.16m are based on a multi-carrier multiple access scheme, applies a multiple input multiple output (MIMO) to improve transmission efficiency, and uses various technologies such as a beam-forming method, an adaptive modulation and coding (AMC) method, a channel sensitive scheduling method. The above-mentioned technologies improves transmission efficiency by a method for intensifying transmission power transmitted from several antennas or controlling the transmitted amount of data depending on channel quality, or the like and transmitting selectively data to a user having good channel quality, thereby improving system capacity performance.
Since most of the techniques are operated based on the channel state information between an evolved node B (eNB) (base station (BS)) and a terminal (user equipment (UE), mobile station (MS)), the eNB or the UE needs to measure the channel state between the base station and the terminal. For this purpose, a channel state indication reference signal (CSI-RS) is used. The above-mentioned eNB means a downlink transmitting apparatus and an uplink receiving apparatus that are positioned at a constant place and one eNB performs transmission/reception to and from a plurality of cells. In one mobile communication system, a plurality of eNBs are geographically dispersed and each eNB performs transmission/reception to and from a plurality of cells.